The colour wheel is build up of three types of colour: primary colours, secondary colours and tertiary colours

Primary Colours
The primary colours are red, yellow and blue. It is not possible to make any of these three colours by mixing colours together.

Secondary Colours
Secondary colours are made by mixing two primary colours together in equal quantities, for example yellow and blue make green.

Tertiary Colours
Tertiary colours can be created by mixing one primary colour and one secondary colour from the same part of the wheel.